Development of Atom Counting Technique by Laser Ionization

1997 ◽  
Vol 3 (S2) ◽  
pp. 1077-1078
Author(s):  
S. Ichimura
Keyword(s):  
High Vacuum ◽  
Input Pulse ◽  
Laser Ionization ◽  
Ion Imaging ◽  
Spherical Lens ◽  
Electron Multiplier ◽  
Imaging Detector ◽  
Input Pulse Energy ◽  
Ionization Region ◽  
Atom Counting

The aim of the present study is to discuss the possibility of “counting atoms” by laser ionization technique, which has been applied to post-ionization in sputtered neutral mass spectrometry. The detection of one H2 molecule was tried under an extremely high vacuum (XHV) condition, since the molecule has a higher ionization energy (15.4 eV) than most of elements and the existence probability of it within laser ionization region is less than one under the condition.Fig.1 shows schematically the experimental setup. The second harmonics (SH) of a picosecond YAG laser was focused with a spherical lens (f=250 mm) into the center of a home-made XHV chamber (Fig. 1a). The focused laser power density (W) is more than 1013W/cm2 for input pulse energy of 30 mJ, and the saturation of H2 ionization can occur under the condition. The repetition rate of the laser was 10 Hz. The XHV chamber can be evacuated to a minimum pressure of 5×10−11n Pa. To the chamber, either an ion counting detector or an ion imaging detector was attached. The ion counting detector (Fig.1b) is composed of ion collecting electrodes, an electron multiplier (EM), and a pulse counter.

Shadowgraphic Imaging of Dilute Carbon and Mo2Ag4S8,[PPh3]4 Suspensions

1997 ◽  
Vol 479 ◽  
Author(s):  
Robert Goedert ◽  
Roger Becker ◽  
Andrew Clements ◽  
Thomas Whittaker
Keyword(s):  
Carbon Particle ◽  
Input Pulse ◽  
Laser Pulses ◽  
Focal Volume ◽  
Time Resolved ◽  
Nonlinear Materials ◽  
Input Pulse Energy ◽  
Laser Induced Breakdown ◽  
Plasma Absorption ◽  
Keywords Laser

AbstractTime-resolved imagery is presented showing the changes that occur in the focal volume of dilute liquid/particle suspensions following the arrival of single, Q-switched, frequency-doubled, Nd:YAG laser pulses. Limiting data and corresponding imagery at 21, 84, 244, 790, and 2900 nanoseconds following the laser pulse are presented for a carbon particle suspension consisting of used (carbonized) 1OW-15 motor oil and for a suspension of the inorganic metallic cluster molecule Mo2Ag4S8 [PPh3]4. The images in conjunction with the accompanying limiting data show that the reduction in transmission, observed as the input pulse energy is increased, results from scattering from bubbles augmented by plasma absorption. Keywords: laser induced breakdown, plasma, suspension, bubble, nonlinear materials, shadowgraph, imagery

Generation of 1.30- to 1.55-μm Tunable Radiation from First Stokes Raman Shifting in Hydrogen

1997 ◽  
Vol 51 (6) ◽  
pp. 820-826 ◽  
Author(s):  
Kenneth W. Aniolek ◽  
David L. Miller ◽  
Nicholas P. Cernansky ◽  
Kevin G. Owens
Keyword(s):  
Pulse Energy ◽  
Near Infrared ◽  
Input Pulse ◽  
Dye Laser ◽  
Beam Diameter ◽  
Input Pulse Energy ◽  
Stokes Lines ◽  
Anti Stokes

Raman shifting to the near-infrared, when possible, provides a simple and economical alternative to the optical parametric oscillator (OPO) or difference frequency mixing approach. We report the production of 1.30- to 1.55-μm radiation from first Stokes Raman shifting in a single-pass, open (no capillary waveguide), hydrogen-filled Raman cell (constructed in-house) pumped with a Nd:YAG/dye laser combination operating near 900 nm. A maximum of 10 mJ (19% efficiency) of first Stokes energy was measured for the highest cell pressure (490 psia) and input pulse energy (53 mJ). The quality of the first Stokes output is similar to the dye laser output as indicated by polarization, shot-to-shot energy fluctuation, beam diameter, and linewidth. A characterization of the Stokes and anti-Stokes output was also conducted including one-dimensional spatial intensity profiles and output line dependence on input pulse energy and cell pressure. A large first Stokes conversion efficiency has been attributed to little production of higher-order Stokes and anti-Stokes lines.

scholarly journals Simulation Study of Mid-infrared Supercontinuum Generation at Normal Dispersion Regime in Chalcogenide Suspended-core Fiber Infiltrated with Water

2020 ◽  
Vol 30 (2) ◽  
pp. 151
Author(s):  
Bien Chu Van ◽  
Mai Dang Ngoc ◽  
Van Cao Long ◽  
Hoang Nguyen Tuan ◽  
Hieu Le Van
Keyword(s):  
Optical Fibers ◽  
Input Pulse ◽  
Supercontinuum Generation ◽  
Mid Infrared ◽  
Normal Dispersion ◽  
Infrared Wavelength ◽  
Dispersion Regime ◽  
Input Pulse Energy ◽  
Core Fiber ◽  
Air Hole

We report simulation results of supercontinuum generation in the suspended-core optical fibers made of chalcogenide (As2S3) infiltrated with water at mid-infrared wavelength range. Applying water-hole instead of the air-hole in fibers allows improving the dispersion characteristics, hence, contributing to supercontinuum generations. As a result, the broadband supercontinuum generation ranging from 1177 nm to 2629 nm was achieved in a 10 cm fiber by utilizing very low input pulse energy of 0.01 nJ and pulse duration of 100 fs at 1920 nm wavelength.

scholarly journals Extremely-high vacuum system for the pressure measurement using the laser-ionization method.

Shinku ◽  
1991 ◽  
Vol 34 (1) ◽  
pp. 14-16 ◽  
Author(s):  
Kiyohide KOKUBUN ◽  
Hazime SHIMIZU ◽  
Shingo ICHIMURA ◽  
Humio KAWAHARA ◽  
Minoru KONDO
Keyword(s):  
Pressure Measurement ◽  
High Vacuum ◽  
Vacuum System ◽  
Laser Ionization ◽  
Ionization Method

scholarly journals Development of a cold-neutron imaging detector based on thick gaseous electron multiplier

2013 ◽  
Vol 84 (2) ◽  
pp. 023305 ◽  
Author(s):  
M. Cortesi ◽  
R. Zboray ◽  
A. Kaestner ◽  
H.-M. Prasser
Keyword(s):  
Cold Neutron ◽  
Neutron Imaging ◽  
Electron Multiplier ◽  
Gaseous Electron ◽  
Imaging Detector

Analysis and Speciation of Lanthanoides by ICP-MS

2016 ◽  
Vol 1 (11) ◽  
Author(s):  
Lena Telgmann ◽  
Uwe Lindner ◽  
Jana Lingott ◽  
Norbert Jakubowski
Keyword(s):  
Inductively Coupled Plasma ◽  
Dynamic Range ◽  
Matrix Effects ◽  
High Vacuum ◽  
Argon Plasma ◽  
Ion Source ◽  
Mass Analyzer ◽  
Electron Multiplier ◽  
Inductively Coupled ◽  
Icp Ms

Abstract Inductively coupled plasma mass spectrometry (ICP-MS) is based on formation of positively charged atomic ions in a high-frequency inductively coupled Argon plasma at atmospheric pressure. The ions are extracted and transferred from the plasma source into a mass analyzer operated at high vacuum via an interface equipped with a sampling and a skimmer cone. The ions are separated in the mass analyzer according to their charge to mass ratio. The ions are converted at a conversion dynode and are detected by use of a secondary electron multiplier or a Faraday cup. From an analytical point of view, ICP-MS is a well-established method for multi-elemental analysis in particular for elements at trace- and ultra-trace levels. Furthermore, methods based on ICP-MS offer simple quantification concepts, for which usually (liquid) standards are applied, low matrix effects compared to other conventional analytical techniques, and relative limits of detection (LODs) in the low pg g−1 range and absolute LODs down to the attomol range. For these applications, ICP-MS excels by a high sensitivity which is independent of the molecular structure and a wide linear dynamic range. It has found acceptance in various application areas and during the last decade ICP-MS is also more and more applied for detection of rare earth elements particularly in the life sciences. Due to the fact that all molecules introduced into the high temperature of the plasma in the ion source were completely dissociated and broken down into atoms, which are subsequently ionized, all elemental species information is completely lost. However, if the different species are separated before they enter the plasma by using adequate fractionation or separation techniques, then ICP-MS can be used as a very sensitive element-specific detector. We will discuss this feature of ICP-MS in this chapter in more detail at hand of the speciation of gadolinium-containing contrast agents.

High-Vacuum Tribometers: State of the Art and Current Developments

2008 ◽  
Author(s):  
G. J. Molina ◽  
C. Kajdas ◽  
M. J. Furey ◽  
R. McDaniel
Keyword(s):  
Surface Science ◽  
State Of The Art ◽  
High Vacuum ◽  
Photon Emission ◽  
Photon Counting ◽  
Kelvin Probe ◽  
Electron Multiplier ◽  
Surface Work ◽  
New Type ◽  
Evolution Dynamics

This paper reviews the application to tribology research of the techniques of high-vacuum surface science, in particular their integration into high-vacuum tribometers. The state of the art, the varied research interests, and the rationale for requiring such research instruments are discussed. The authors have developed a new type of high-vacuum tribometer that is aimed to the detection and characterization of charged-particle triboemission. This tribometer has been successfully used to count triboemitted charges as channel-electron-multiplier pulses and their energy distribution from different material pairs (i.e., ceramics and semiconductors when scratched by a diamond pin, and ceramics-on-same-ceramics). Instrument enhancement is ongoing to include simultaneous under-vacuum photon counting and surface work-function measurement by Kelvin-probe. The enhanced facility will enable one-of-a-kind experiments by characterizations and correlations of electron and photon emission, and of surface property evolution dynamics during sliding contact.

A micropixelated ion-imaging detector for mass resolution enhancement of a QMS instrument

2014 ◽  
Vol 407 (8) ◽  
pp. 2055-2062 ◽  
Author(s):  
Sarfaraz U. A. H. Syed ◽  
Gert B. Eijkel ◽  
Simon Maher ◽  
Piet Kistemaker ◽  
Stephen Taylor ◽  
...  
Keyword(s):  
Resolution Enhancement ◽  
Mass Resolution ◽  
Ion Imaging ◽  
Imaging Detector

scholarly journals Temperature and Pulse-Energy Range Suitable for Femtosecond Pulse Transmission in Si Nanowire Waveguide

2020 ◽  
Vol 10 (23) ◽  
pp. 8429
Author(s):  
Xiaochun Wang ◽  
Meicheng Fu ◽  
Heng Yang ◽  
Jiali Liao ◽  
Xiujian Li
Keyword(s):  
Energy Range ◽  
Pulse Energy ◽  
Femtosecond Pulse ◽  
Input Pulse ◽  
Silicon On Insulator ◽  
Oxide Semiconductors ◽  
Optical Gating ◽  
Pulse Transmission ◽  
Input Pulse Energy ◽  
Different Temperatures

We experimentally measured the femtosecond pulse transmission through a silicon-on-insulator (SOI) nanowire waveguide under different temperatures and input pulse energy with a cross-correlation frequency-resolved optical gating (XFROG) measurement setup. The experimental results demonstrated that the temperature and pulse energy dependence of the Si photonic nanowire waveguide (SPNW) is interesting rather than just monotonous or linear, and that the suitable temperature and pulse-energy range is as suggested in this experiment, which will be valuable for analyzing the practical design of the operating regimes and the fine dispersion engineering of various ultrafast photonic applications based on the SPNWs. The research results will contribute to developing the SPNWs with photonic elements and networks compatible with mature complementary metal–oxide–semiconductors (CMOS).

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